Victoria Magnetics transformers for Aleph-X (or others)

[jwb]

Several people have commented on the Aleph-X thread that they have contact Victoria Magnetics. I have also. John at VM was enthusiastic and quoted $65-68 for 500VA, 22V secondaries. This would be about the right voltage and more than enough power rating for an Aleph-X with +/-12V rails and quite a lot of bias current.

Should I arrange for larger quantity of these?

[Peter Daniel]

You mean center tapped 22V?

[Taco]

Don't you get after rectifing to much voltage ?? (Sorry voor newbie question)

[fcel]

Didn't a few other guys from this forum tried to gather a group order together to purchase transformers from Victoria Magnetics for the Aleph-X project?

[jwb]

Right. I should have been more specific. With the 22V secondaries and a single bridge rectifier, you will get around 14V on the rails. Many designs seem to be in the 12-15V range so I thought this was appropriate.

In my design, I have a CRCRC filter which drops 2V, therefore I get 12V on the rails.

As for center tapping, I am indifferent. I'll take either a single secondary with the correct ratings, dual secondaries in parrallel, or dual secondaries in series.

[MikeW]

I would like something in the 500-600 VA range, 110 volts in, Dual seconderies @ 15 Vac. That would give me +/- 21 volts DC with a rectifier for each channel. I was going to us the regulator from the Zen V3 article (approx. 4-7 volt drop depending on how you build it). Do you have a standard product that you were going to offer for this amp? I don't need to use the regulator. It was just a thought.

This is the message I sent to John. But if you have better solution I will get in on a group buy.

[hifiZen]

I've been in contact quite a bit with John from VM, discussing transformers for the Aleph-X, and group buy options. He's indicated to me that he can do some sort of standard part for people to order direct from him, which would seem preferable to large group buys, with all th associated double-shipping costs and organization effort etc.

As far as the transformer specs go, he says they use a standard core size for toroids in the range of 300VA to 500VA, and that this core is actually good to over 600VA, so it's a little overrated. He also mentioned that it would not be a problem for him to wind different secondary voltages since he knows that people will want different rail voltages, and power supply filter configurations.

[Peter Daniel]

Sounds like a good idea.

[roddyama]

I'd be in for a couple of mono-block transformers in that range as long as I can (as Chad said) pick my output voltages. Maybe more if I get ambitious.

Rodd Yamashita

[Edwin Dorre]

Originally posted by jwb
Right. I should have been more specific. With the 22V secondaries and a single bridge rectifier, you will get around 14V on the rails. Many designs seem to be in the 12-15V range so I thought this was appropriate.

In my design, I have a CRCRC filter which drops 2V, therefore I get 12V on the rails.

Sorry,

I used for my 6.8A biased Aleph-X :

Toroidal power transformer 1000VA typenumber Z8015 Euro 151,74
Primary 230V
Secondary 22V 22.73A - 22V 22.73A

With IR MBR-2045 rectifiers and 6 times 22000uf 63V and CRCRC with R=0.11 (I lost about 0.77V each R at I=6.8A). With a load of 400W on this transformer I got a DC of about +25V and -25V ....

Not even close to your 12V!!!

Edwin